Camera control



Oct. 31, 1950 D. B. DORSEY ,Q 2,527,800

CAMERA CONTROL Filed Aug. 19, 1947 v 7 Sheets-Sheet 1 IN VEN TOR.

Zia/26.512 Z0259 Oct. 31, 1950 D. B. DORSEY 2,527,800

cm comer.

Filed Aug. 19, 1947 Sheets-Sheet 2 K54 INVENTOR.

545 rg ffizziiz. 20755? M %au)/ D. B. DORSEY CAMERA CONTROL Oct. 31, 1950 '7 Sheets-Sheet 3 Filed Aug. 19; 1947 INVENTOR. Zara/2x5121707 BY m Oct. 31, 1950 o. a. DORSEY 2,527,800

cm cou'mor.

Filed Au 19, 194;: V '1 SheetS- Sheet 4 IN V EN TOR.

Oct. 31, 1950 I DQRSEY 2,527,800

CAMERA CONTROL I Filed Aug. 19, 1947 Sheets-Sheet 5 IN V EN TOR.

Oct. 31, 1950 n. a. DORSEY 2,527,300

CAMERA CONTROL Filed Aug. 19, 1947 7 Sheets-Sheet 6 D. a. DORSEY cm CONTROL Oct. 31, 1950 I 7 Sheets-Sheet 7 Filed Aug. 19, 1947 l atented Oct. 31 156 UNITED STATES PATENT OFFICE CAMERA CONT-ROD Dennis E. Dorsey, Chicago, I ll. Application August 19, 1947', Serial No. 769,465

This invention relates to camera controls.

1 It is a principal object of this-invention to provide an automatic camera wherein means is provided for initially setting the control according to film speed ratings and means thereafter operable automatically to control the setting of the shutter opening in accordance with the adjustment of a member to determine the'prevailing light conditions.

It is a further object of the invention to provide in such anautomatic camera, means automatically varying the shutter opening in accordance with adjustment of. the shutter speed and so constructed that setting of the shutter speed is automaticallylimited by the maximum and. minimum shutter openings capable of being used under the prevailing light conditions.

It is a further object of theinvention to .pro-

.vide in a camera having exposure metering means, means controlled by the metering means to determine the proper shutter openings and time intervals for the taking of time exposures.

A still further object of the invention is to provide in a camera having time exposure timer, means initiating the operation of the timer on opening of the shutter to take a time exposure and means automatically operable by :the timer to close the shutter to terminate the time exposure.

A moreyspecific object of the invention is to provide an automatic camera light measuring means comprising a pair of light varying filters cooperating 'with a variable density screen,

wherein one of the filters has portions of different range oflight transmissibility and is connected to shutter speedcontrol means, while the other'filter has a single range of light transmissibility and is connected to shutter opening control means.

Other and further objects and advantages of the invention will be apparent from the following description when taken with the accompanying drawings wherein:

Fig. 1 is a view in side elevation of a camera provided with a control embodying the present 45 section and partly in elevation, of the control of Fig. 1; a l Fig. 4 is a fragmentary view in side elevation opposite that of Figure 1;: l

Fig. 5 is a fragmentary enlarged view of the control of Fig. 1 and with the housing being cut;

a 5 Claims. (01. 95 -40) away and shown invertical section to expose the parts mounted therein;

Fig. 6 is 'a view in vertical section taken-substantially along the line 6-6 of Fig; 5;

Figs. '7 and 8 are related views in exploded per spective showing certain essential parts of the control unit of Fig. 1;

Fig. 9 is. a view in vertical section taken along the line 9-9 in Fig. 10;

Fig. .10 is a view in vertical section taken along the line Ill-I0 in Fig. 9;

Fig. 11 is a view in exploded perspective of a shutter assembly forming part of the camera control of Fig. 1;

Fig. 12 is a perspective view of a control means forming part of the camera control of Fig. l;

. Fig. 13 is a view in vertical section taken along the line l3-l3 of Fig. 5;

Fig. 14 is a fragmentary view in vertical section taken along the line I l-l4 of Fig. 5;

Fig. 21 is a view in vertical section taken along the line 2l 2| of Fig. 3;

Fig. 22 is a fragmentary view in vertical section taken substantially along the line 22'-22 in Fig. 19;

Fig. 23 is a fragmentary side elevational view similar to Fig. 4, showing a second embodiment of the invention;

Fig. 24 is a sectional view taken on line 24--24 of Fig. 23; and

Fig. 25 is a detail sectional view taken on line 25-25 of Fig. 23.

Although as shown in Fig. 1, the camera control unit2 embodying the present invention is secured to a camera 4 having cooperating view finder prisms 6 and 8 and a viewing lens It! with sight piece I2, it is to be understood that it may be secured to, or incorporated in any camera having a lens tube 14, Fig. 3, projecting from the box IE, or bellows, of the camera. As shown best in Fig. 3, the camera control unit 2 prefer- .ably comprises anexposure meter unit consisting the base of thedrum.

A time exposura'interval timer 46, Figs; 5 and 13, is mounted in thejrearfipaift 26 of the houssecure the parts post.

screen 22 and a viewing tube 24, the filter 20,

screen 22 and tube 24 being mounted in an external housing comprising a rear part 26 and a forward part 28. V,

The rear housing or part 26 consists of a drum mounted on the lens tube I4 of the camera and secured against the front wall of the camera by a ring 30 threaded or press-fitted on the lens tube I4. The drum has an annular external flange 32 (Fig. '7) having an arcuate slot 34, and having its forward edge bent or spun inwardly to form a radial shoulder and an annularseat 36 for the.

forward part 28 f the housing. The viewing tube 24,, Figs. 3 and '7, is provided at its inner' end with an annular flange 38, spot welded or otherwise fastened to the drum in line with the opening 40 of the .viewing tube. A mountingcoaxial with lens tube I4, and a smaller opening II4, coaxialwith, and receiving, the forward end of the viewing tube 24 of the exposure unit.

The light screen 22' consists. of a translucent disk which is provided with a tri-density pattern or-field of view, as best shown in Fig. 14, for the post 42, Figs. 7, 9 and 10, carries an annularf flange 4 spot welded or otherwise fastened at ing, This time exposure timer preferably comprises an escapement wheel 48 controlled by an H adjustable escapement 56 and controlling a-series of the usual clock gears 52, 54, 56 and 58. Apin 60, secured to the base of th drum 26 forms a 'pivot for the escapement 50, controlled by a spring 62 which bears at one end against the escapement and at the-otherend against a collar 64 secured. to a set screw'lifi projecting from an opening in an indented portion '68 of the flange "32 of the drum." The set' screw 66 may be adjusted to' control the spring pressure on the escapement and hence the speed of the timing mechanism. The gear 58 is'journalled on the post 42 (Figs. 7, 9 and and has secured to it, as by pins or rivets; adrum lll, to the flangev of which is secured an internally toothed ratchet I2. A pawl I4 cooperates with the ratchet l2 and is pivoted on a pin securedto a gear 16, also journalled on the post 42;? Afs'pr'ing 18, secured to the gear I6, urges 'the pawloutwardly. into engagement with the ratchet. spiral spring I I9, pinned at one end telthegar I6 andsecured at its other end to the sta'tionary post 42, urges the gear 76in a clockwisedire'ction, as seen in Figs, 9 and 13. The hub of the gear I6 and a collar 00 pinned to the outer end of the post 42, in assembled relation on the The gear'liimeshes with gearteeth 82 formed on the ring portion 06 of atim'e exposure control device 85, journalledon a reduced portion 86 of the ring'30, on which it isheld against axial movement by a collar 88, fitted or threaded on the end of'thering 30. Ifhe ring 84,'a's best seen in Figs. 7 to 13, is formedwith a radial arm or segmental portion 90, provided with' an arcuate flange portion 92. r-lnoperating pin 94, secured to the flange 92, projects through the slot 34 of the drum. 26, and the arcuate flange 92 is inscribed below the operating pin 94with suitable timing indicia 96.

The forward edge of the arcuate flang tending in a counter-clockwise. direction from an inwardly bent and forwardly directed cam lug I00. The ratchet teeth 98 cooperate with a pawl I02, Figs. 5 and '7, formed on the outer .end of th arm I04 of the shutter release I06. i

The forward portion 28 of the housing comprises a cylinder, as best shown in Fig. 7, seated on the, depressed flange 36 (Fig. 3) of the drum 26 and secured thereto in any convenient man-e 92 is formed with'serrations or ratchetteeth 98 exhaving at itsouter end arearwardly bent oper- 'afting lugMZ'eXte'nding through an arcuate slot .ph'ragmaticlem'rs 'I 4I8;are mounted between the exposureunit. This tri-density pattern consists,

preferably of an opaque cross II6 upon a white 'or transparent background IIB, surrounded by an opaque ring I20, in turn surrounded by a gray annulus I22. 1 r

' A single diaphragmatic shutter mechanism I24 is utilized to determine both the size of-the aperture opening and the timing'of-instantaneous-iex posures. This .rsh'utter: mechanism preferably comprises a drum shaped' housing I26, best seen in Fig. 8-,and has an annular flange I28 by means of which the housing is mounted on "the forward faceof the central mounting plate I08.

The housing is provided with a central opening coaxial with the opening I I2 in the plate 100 and with the lens tube 14.; A front lens tube I30 is secured inthat opening of the housing I26 and is internally threaded, asbest seen in Fig. 3, to receive the externally threaded mounting stud of the usual front lens moun'tfil 32.

Within the housing I26 is ated a shutter I34 and a camflipfi'wh ich'controls the size of the shutter opening by determining the extent of opening movement of theshutter. The shutter I34 consists ofa'shiitable ring"or disk I38 jour: nailed in'the drum housing I26 and provided with a laterallyprojecting operating lever I40,

I44 '(Fig. '7), in the periphery ofthe mounting plate I 08 for engagement with, and operation by,

the shutter operating and timing mechanism magne V e M A plurality of blades or leaves "Md-of a shape best seen in Figs. 11 andl9 to 21, are secured by 'pins 'or rivets I50, .to' a stationary ring 152?,Q0-

axial with, and smaller than, the ring I38 and 5 mounted in the sameplane as theringI-ifl. The

ring I 52 is fastened to 'thejorwar'd face of the mounting plate lfla'by the pins kor rivets I50, whicnalsosecure airing 154 to the sing I52, but in spaced axial relation thereto so that the. dia-- rings I 52 and 154.

- The blades I48 may takea numberofdifferent shapes. They are, however, each provided with an arcuate edge -I 5.6, the radius .of which is equal to the radius of the largest desired shutter opening, and are provided with :tongue .portions i58 which are of suchrlengthqas .to overlap and ex clude all light when the blades are in closed posi- 7 tion. -Theinneredgesofthe tonguesI58 provide arcuate extensions J60, of thearcuate edges 5 56 -of the mainbodiesof the blades, and the blades aremounted on therings I52 and .I54 in the usual inter-leaved relationship; The outer ends of the blades extend beyondthering I52 and over the ring I38. Headed .pinsorv screws I52, carried by the shiftablefring I38, ;are received. inenlarged .1 holes or slots [64'in theloutenends of -.the.bla,des

I48""so 'that when'the [38 is rotated ma I38 isurged in the clockwise direction, as seen in Figs. 8 and 19 to 21, by a pair of springs I66 (Fig. 14), received-in radial recesses I68 of mounting plate I08 and mountedo'n' pins I10 secured to the stationary ring I52. One end of each spring bears against a pin I12 mounted on the ring I52, and a pin I14 secured to the shiftable ring I 38; The ring I54 is provided with a notched annuf: lar flange I16 in which is journalled control cain -'I36, havingan internal cam surface I18 for en gagement by a lug I80 secured to one of the shutter bladesl48. The lug I80 projects through a slot I82 in the internal margin of the ring I54. The control cam I36 has secured to,"or formed integrally with it, a radially operating lever I84 which is resilient orflexible in a direction axially of the cam'. This lever is'p-rovided on its forward face with a tooth or clutch element I86. Lever J84 projects out of thehousing I26 through a slot I88 in the rim of the housing and forwardly from the plane of thecam so that the tooth I86 may engage the serrated edge I90'of the adjustable wheel or disk I92 (Figs. 1' to 5 and 8) of the exposure meter unit. The wheel I92 is journalled on the forward lens tube I30, and closes the forward end of the housing formed by the drum 26 and cylinder 28.

It should be noted that the internal cam surface I18' of the control cam I36 serves as an adjustable stop for the lug I80 of the shutter. Therefore, the angular position of the control cam I36 relative to the shutter blade mounting rings I52 and I54 determines the size of the exposure opening.

- .A shutter speed setter, or control, device I 94 (Figs. 3,5 and 8) comprises a segment I96, having a central hub portion I98 journalled on the forward lens'tube I30, and a shutter speed control cam 200 (Figs. 3, 5 and 7) which consists of a ring 202, having arcuate slots 204receiving headed mounting screws 206 (Fig. 3) threaded into angularly spaced openings in the mounting plate I08.

The disk 202 is spaced from the mounting plate "by spacing cylinders 208 mounted on screws 206 and interposed between the cam and the plate. The ring 202 is provided with an external cam. surface 2I0 to control the setting of an interval timer 2I2, Fig. 6. 7 It is also provided withan operating lever which consists of a portion 2? projecting radially from the ring 202, an axially and cooperates with substantially conventional shutter control or operating means 222, Figs. 6 and '7. Lever I06 is pivoted on a pin 224 to the rear face of the central mounting plate I08. It is urged in a clockwise direction by the usual spring 226 mounted on pin 224. The lever I06 cooperates with the 'usual pair of checking levers 228 and 230 which control th shutter for bulb and timeexposures, respectively. These levers are pivoted on pin 232 secured to the rear face of thernounting plate I 08. "Each is urged in a counterclockwise direction, as seen in Fig. 6, by the usual spring 234 (one only being shown) mounted on the pin 232. The release lever I06 also cooperates with the usual tripping lever 236 journalled on a pin 238 secured to the rear face of the mounting plate I08 and urged in a counter-clockwise direction by a spring 240 mounted upon pin 238 and engaged at one end by the lug 242 of the lever I06, and at its other end by a fixed pin 244 secured to the mounting plate I08. The tripping lever 236 in turncooperates with the usual shutter control lever 246 journalled on a pin 248 secured to the rear face of the mounting plate I08, and

.urged in a clockwise direction by a spring 250 mounted on the pin 248 and engaging a fixed pin 252 and a lateral lug 254 on the lever 246; The lever 246 at its outer end engages the axially projecting portion I42 of the shutter operating lever I40: A

The lever246 is moved in a counter-clockwise direction, as seen in Fig. 6, to release the lever I42, by means of a lateral lug 256 on the tripping lever 236. The lever 236 is also provided with an inturned end 258 seated between the furcations of a bifurcated lever 260 which constitutes the time or speed controlled lever of the timing mechanism M2. The extent of the setting of lever 260 is determined by the engagement of lateral lug 262 of the lever 260 with the external cam surface 2 I 0 of the control cam 200. The lever 260 is provided with a gear segment 264 which meshes with a gear 266, the gear being controlled by escapement wheel 268 under control of the escapement 210, and the lever is set and urged in a counter-clockwise direction by the usual spring 212. The cam 20-0, in determining. the permissible rotation of the lever 260 in a counter-clockwise direction, determines the time required for the lever to be returned in a clockwise direction to the position at which it will release the lever 236. It thereby determines the time at which the lever 236, in rotating in a counter-clockwise direction will release the actuating lever 246, so that the latter will be rotated in a clockwise direction .by the spring 250. The spring 250 is of greater force than the springs I 66 which move the shutter blades to open position, and therefore, when it is permitted to return the lever .246 in a clockwise direction, that lever will, by engagement with the end I42 of the shutter lever I40, restore the shutter to closed position. a g The tripping lever 236 is rotated in a clockwise direction by the lever I06 which, for that purpose, is provided witha lug 214 which engages the pointed end of the lever 236, but passes beyond and frees the lever 236 for return by the control timing mechanism 2I2 when the lever 236 has been rotated through a predetermined angle in a counter-clockwise direction. Lever I06 is rotated in-a counter-clockwise direction by the usual spring returned, exposure button 216 mounted in the usual manner in the bushing 218 projecting through the cylinder 28, the button 216 engaging the handle I04 of lever I08.

, In the taking of a bulb exposure the lever 236 is held against return movement by the checking lever 228, the end lug 284 of which engages in the 7 leased.

- 7 In thektaking' off'a time exposure, the e gposuse button 216 must be depressed. e; the first dess opening th hu tennd the.- second depression closing. the shutter, held in shutter-openingposition during the time exposure, by the end ofrzthe lever23UWhich ,e ngagesin theusual manner-the forward-edge of the lug 280 of the lever 236.: The lever 2311 s, so

' shaped, in the usual mannerythatiwhenLit checking engagement with the ,leverE-236 it looks "the'lever: I06 in a. partially; depressed position;

TOnthe second depression. of the exposure button 216, the lever I06, which is provided :with-ailug 286 engaging the underitisu-rface-ihf clevers, 2'28 and 230, moves thel'ever23lJ-:out;o'f engagement with the lever 236 soithat the 'shutterds 'there upon'closed..:. .1- Levers 230? and 228' are rendered; inefi ective during thetaking of instantaneous exposureszby a cam 288fsecured to agear 290, journalledion a pin-292 carried by the mountingplate I383= The :gear 298 meshes withgearteeth '294 formed on the periphery of the cam disk 2116' so that moves into the arcuatenotchfisfi,while"the lug 238 is still restrained by engagement with'the enlargedperipheralsurface of the'cam. When the cam 288 is set for the taking of 'a timee g posure, both lugs'29 8 an'd30ll are freed fromthe surface of the cam for movement into the arcuate notch 29B. h I

An internally threaded bushing 35,2, projecting through the central part-28 of the housing in axially spaced relation to thebushing 218, receives the usual cable release 304which upon operation of the cable release button engages and depresses the arm jtl l of the exposurecontrol lever I96.

The shutter speedgsetter itl also srvesas an {adjustable means measuring in tensity, and .for that purp se" isprovidedjwithjan arcuate slot 305 (Fig. '8; n ts segmentalflportion I93, in which slot. is; mounted the light measur.- ing filterjzil. This"lightrn asuringjilter 26fpreferablyfcomprises a. polarizing filter hav n a 1111i? gfor'm opacity section 33% and a clear section. 3H3,

theunifor n'opacity. sectign etc being. utilized'to measure lightintenSitiesiorI' the making of in.-

' stantaneous exposures, andthe clear section SID being utilized ifor the making of lim t and bulb exposures. The. shutter speed setter andflight measuring device I 9,4is provided with an ,opei-.at-

ing or adjusting lever 3| 2,. integrally Iormedwith,

orl securedlto; the..segmental portion .I 96. Pref erablyjithe' lever 3I2'is formedor secured to'a portion 3I4 joined at its base to the segmental portion I93, but Separated .alo'ngits sides by radial cuts 3 I 6 so that the portion 3I'4may be defiected laterally of the plane of v the segment I98, but is sufiicien'tly-resilient to'bej returned intothe plane of the segment when the lever 3I2 is reh l v r -2 iS r l hedlever 3L2 {extendsradially from the seg:

ment I93 and-passes out of the housing cylinder za throughan arcuateslot 3I'8' (Fig.7) which is in cdrnmunicationwith; axially. directed slots 320, the surface of the-cylinder adjacent the slets being inscribed withsuitable shutter speed:

dicia 322 representing fractionalparts of a outlier-the taking of instantaneous exposures The longest slot 320-, i .e., the one-fifthof-a second slot, .is also, in. communication with an arcuate "slot'3-24, the. surface of the cylinder adjacent slot 324 being provided with angularly spaced indicia l3 7 :and iT, representing bulb and time exposure settings, I V

The resiliently mounted lever 3 I 2 is providedon itsforward face with a tooth 326(Fig. '7) adapted to engage, when .the;leyer is moved outof the;

serrated ortoothedledge I90 of the disk or wheel V nalledion the forward lens tube I30." Theradial arm'332 is'secured to,,.orformed integrally with,

the disk 33! and is constructed of relatively thin, fiexiblesheet metal or other material possessing the necessary flexibility; The arm projects from the cylinder 28 of the housing-through an arcuate slot =33;4 (Fig.-7 ),the edges of the cylinder along.

the slot "having serrations or teeth 336-to engage a tooth 338, Fig. 3, carriedby therear: face ofthe slot 346;-;is inscribed with suitable indicia-348 arm 332. The'arm-332 is also provided on its forward face with a tooth 340*adapted to engage the serrations I93 of the wheel or disk I92. I i The. segmental arm 332 of the time exposure guide is provided adjacent its outer edge, which projects beyond the periphery of'wheel I92, with suitable indicia 342 (Figs. 2 and 8) constituting a time exposure scale indicating the, proper exiQOsure timesforthe taking of time exposures at diffierentshutter openings. a Y

a As previously mentioned, the setting lever I84 for theshutter opening control'cam'sI36 extends fromthe shutterhousing I26 through the arcuate slot I38. ;It;a1s o;projects"from the cylinder portion 28 "of- 1711950111361"hOllSiIlg thl0ugh"an arcuate slot 344 (Fig. '7') ,in communication'with a deeper slot343%;The-eurface of the cylinder. '28 along the edge ofthe slot *344, and the base of .the

' itFlgli) constituting a scale of shutter openings indicating the positionyofpthe shutter opening 'controlcam. The slot :344 is-of such depth as to prevent disengagement of the lever from the wheel whiletheqlever is :moving along-the slot, butthe slot :346 is of sufficient depth to allow such disengagement when the *lever is moved down into the base of the slot 346.

An arcuate-lever 350, Figyl2, is pivoted to the innersurfaceiof thecylinder 28, as :by a pin or rivets 35-z -Figs 4,117? and'18; At one end is. a roller 354 which overlies the flexible arm 332 of the time exposure guide. 323,-jso as toengageyand movethe arm forwardly' when the lever 35Ilis movedin a clockwisedirection, as seen in Fig. 4,

and thereby causes -thetooth 33-8 of the armwto bedisengagedfrom-the serrations 336. and the tooth 34!; to. engage with-the serrations I90 of :the wheel I92,thereby couplingtheytime exposure guide to the wheel I92; other end ofthe lever 350 projects across theslot 346. ..Whenever-the lever I8 4-of the shutter opening fcontrol cam is depressed into this slot, the lever 350 willbe rotated clockwise and couple the time jexposure guide to the wheel I92. I Y

The wheel" I92 constitutes primary adjusting means for measuring the light intensity, and for that purpose is provided with an arcuate slot 356 (Figs. 3 and 8) in which ismounted the light measuring-screen I8 which consists preferably of a polarizing filter, the rotation of which, relative to the polarizing filter 2'0, varies the amount of light which is passed to the screen 22.

The polarizing filters -I8 and are so; arranged that one efiects .an increase in the light transmission on clockwise rotation anda decrease on counter-clockwise rotation, while the other efiects a decrease on clockwiserotation and in increase on counter-clockwise rotation. A can 358 having an arcuate central portion and radial end arms circumscribes the top and sides of the .slot 356 to exclude light other than the wanted light for The wheel I92 is provided' the exposure meter. with indicia 360 (Figs. 4 and 8) constituting a film speed scale, as, for example, in Weston speed rating units. The wheel is also provided with indicia 3'62 constituting a shutterfopening The scale 360 cooperates with the lever scale. I84 to determine the proper setting of the shutter .opening control cam for different film speed ratings, and the scale 362 cooperates with the scale 342 carried by the arm 332 of the time exposure guide, to determinethe proper exposure times for the making of time exposures at different shutter openings. It should be noted thatthe exposure guide is shifted only when the lever I84 is depressed into the notch 346 and the wheel I92 rotated to change the film speedsetting of the lever I84. Theexposure guide isso positioned initially that whenever it is coupledtothe wheel the largest shutter opening of scale 362 is aligned with the longest exposure time of scale 3,42. I.

The scale 348 now indicates the shutter opening speed or time of exposure is desired or permissible. Assuming that it is desired to take a picture in #200. or a second, the lever 3I2 is :I IIOVGd axially, and laterally ofthe plane of the disk. l 98, to.disengage the lever 3I2 from the notch320in which it isseated, and the lever 3I2 is then moved arcuately of the slot 3I8 until it is aligned with the slot ,320 corresponding to theriumber 200' on thetiming scale 322. When nthelever is moved .out of the notch 320 in which it was engaged; the tooth 32ii engages the serrated edge of thewheel I92, and therefore, as the lever is moved arcuately along the slot 3I8, the wheelis turned with. it and therefore the front filter I8 and thevrear filter 20 are moved the same angular distance so that the amount of light transmitted through the filters is .unchanged.

The lever I84fof the shutter opening control cam being coupled to the wheel I92, the shutter opening setting is automatically changed in accordance with the changein the setting of the shutter speed. i It, should'ibe noted that the internal cam surface I18 of the control cam I36 The wheel I92 is held in assembled position by a ring 364 threaded on the end of the forward lens tube I30. V

The control unit is used and operates as follows: At the time the film is loaded intothe camera, the lever I84 is moved to,'and depressed into, the notch 346, and the wheel I92 movedrelatively thereto to position the proper film speed rating in alignment with the tooth on the lever.

The lever is then released for recoupling to the wheel. p

r If it is desired to take an instantaneous exposure, the lever 3I2 of the shutter speed setting device I94 is moved, if necessary, to a position in which it is received in one of the notchesj320 V in the surface of the cylinder 28 of the external housing; In this position of the lever, the uni-- form opacity section 308 of. the rear filter 20' of the exposure meter is aligned with the tridensity screen 22.

The wheel I92 is now moved, if necessary, to a position such that the tri-density pattern on the screen 22 may be distinctly seen through the viewing opening I2, or to a positionfin which the pattern on the screen is obscure; The disk is then again rotated in the. oppositedirection .until the gray annulus I22 of the screen pattern just disappears. This change in light represents a given decrease in the amount ofv light;

i. e., a change in the amount of light equal to two units on the ordinary Weston exposure meter. The shutter opening control cam being coupled to the wheel is thus automatically moved to the proper shutter-opening position for the taking of the instantaneous exposure.

8 iii;

car

opening control lever I84 is first positioned to I36 j the proper film speed as before.

the action of the spring 240.

isso shaped that the intervalsbetween the aper- ,tujre indicia-and the speed indicia are of the same magnitude,

The exposure .button 2l6,or the cable release, is now depressed in the usual manner to move therelease lever ,236 in a clockwise direction, thereby swingingthe lever 246 in a counterclockwise direction. Thisreleases the lug I42 of {the shutter control lever I40 and permits the shutter operating spring I66 to rotate the ring I38 of the shutten'thereby-opening the shutter blades to the extent permitted by the engagement ofrthe lug I with the cam surface I18 of the shutter opening control cam I36. Lug 214 ofthe shutter. actuating lever I06 passing beyond the end ofthe lever 236, the latter is immediately released by lever I06 for return movement in a counterclockwise direction against However, the returnof the lever 236 is delayed by the timing mechanism 2I2, the. time setting of which is determined,.as previously described, by the set- 0 ting;of.the shutter speed control cam 200 in dependence upon the shutter speed settin device. I94. The. proper ,fractional time interval having elapsed, thelever 236 is released by the timing mechanismand returns to its original position,,permitting the'lever 246 to be swung in a clockwise direction and engage the lug I42 of theshutter actuatinglever I40 so as to move the shutter to' closed position against the action of the shutter springs I66.

In the taking ,of a bulb exposure the shutter However, the shutter speed setting device I94 is now rotated until it reaches theone-fifth of a second notch l anjd .then uncoupled from the wheel and the .moved back to B position.

I92 the lever aperture proper for the longest time interval of which the interval timing device is capable.

7 1-1 l'ever 3I2 moved along thearcuateslo't I324""to the time or T position. In movin relative to the wheel fromthe one-fifth of a secondf'position to the T position, the device I94 positions the clear section of the rear pol'aroid filter 20 in alignment with the viewing tube so that the range of measurement of weak light is increased and a proper shutter opening may be selected.

for a bulb exposure by a measurement ofthe light conditions. The light conditions are now measured as before. A reading is taken from scales 362' and 342, the aperture control lever moved, if necessary, to the position indicated for the chosen time interval, and the lever 3I2 l the lever I84 above plate 366 to maintain the checking lever 230 and to .be released therefrom when the shutter I06 is released, thereby closing v the shutter, the time interval of exposure being guessed as accurately as possible.

In thetaking of a time exposure, the shutter speed setter I94 is first moved into the lower end of the notch 324 corresponding to the time exposureor T position. In moving from the onevU112 extenta properly timed time exposure will be madeautomatically." a I ,Asecond embodimentof a time exposure'scale fisshownin Figs. 23., 24 snags, wherein the time exposure guide plate 328, the lever 350 with its terminal roller354, andthe arcuate notch 334 in lease 28' are eliminated. An arcuatelybent metal plate 366 with'fan' axially bent face 388 is at- .:tached by rivets or other suitable means'to the shutter opening control lever [-84 atafpoi nt, so that it rotates inside case 28.; Arcuate slot 346 in case izalis widened to permit visualization of apportion of plate 365: and onthis portion are inscribed suitable' time indicia 370. A small block 312 with .a, bluntly pointed end is attached to toothed element of lever I84 in engagementwith ,wheel I92, except ,when the lever. is brought opposite the deeper notch346 for the purpose of gdisengaging, lever I84 from wheel I92 in changingifilm ,ratinggsetting. I

-' takingia time exposure, the shutter speed Qc'ont rol lever 3IZ is moved to the T position,

which aligns the clear portion of the back filter with the viewing screen. The combined density of the variable filters is now such that determination of light intensity will-give an automatic calculation of the proper aperture for an ,ex-

fifth of a second position to the time exposure position, the shutter speed setter I94is uncoupled from the. wheel I92 but the rear polaroid filter positioned with its clear section in alignment with the viewing tube. 'The wheel H2 is now rotated" as before, to measurethe light conditions. A direct reading of time and aperture is made from the timing scale 342along the exposure guide and the shutter opening scale 362 on the face of the wheel I92 which together indicate the different permissible time exposure intervals for different selectablejshutter openings. The time exposuresetting and controldefvi'ce 85 is thereafter adjusted,,by movement of the adjusting pin. 94larcuately of the slot 34, to expose at the lower end of the slot '34 the proper timing indici'a 96 corresponding to theltime interval thus determined by the scale 362. This movement of the time exposure setting and control device 85 effects a setting of the time exposure timer 46 and the device 85 is locked in adjusted position by the pawl I02 of the lateral lug I04 of the shutter releaselever I06; The exposure button 216 on the cable release may now be pressed. The pawl I02 is therebymoved radially inward relative to the arcuate section 92 of the time.v exposure setting. device 85 and released fromthe notches 98 on the inner edge shutter release lever I06 and depresses that lever for the second time, thereby-freeing the shutter control tripping lever 236 so that theshutter is .closed, as previously described, to. terminate the time exposure automatically v i It shouldibe noted that when the light intensity has been determined b .rotatingpl'ate I84 will always be set at the Therefore, after. the light intensity has been de termined, if the lever 94 is raised to its fullest posure .of a .given duration, for instance eight seconds, a V

, :I 2,, 10ngeI""fO1 l" shorter {exposure is, desired, a direct reading is made from time scale 31K! and aperture scale 348, and any pair of aperture and time settings maybe chosen.

If other than an eight secondexposure is to be -used the? shutter opening control lever I04 ,is moved to thechosensetting on scale 348 andthe :sliutter" is opened for the required time, either by a*bulbj exposureyor by setting the time exposure tim,

' time exposuref Since the automatic time exposure timer can lever 94 ,of the'timi ng device be elevated to its fullest "extent a, prop r fimfii time exposur will be ma e automatically. 1

in the form, construction and arrangementof the parts without departing from thespirit of the invention or sacrificing any of its advantages,

and the right is hereby reserve'd to make. all such ing movement of the shutter, a speed control member for..d,etermining the time between the openingand-closing of the shutter,- exposure metering means comprising/a screen having atridensity-pattern for determininga standard light intensity, a first polarizing filter adjustably mounted tovarythe transmission of light to said screen, means connectingsaid first filterto said shutter speed controlmeans to vary the speed of the shutter in dependence-upon the setting of said filter, secondpolarizing filter cooperating with the first tovary thetransmissionof light to the screen,.means adjustably connecting saidsecondfilter to said shutter opening control means for movement therewithto setsaid control r andtalting an f automatically timed It will be obvious that changes may bemade for connecting said guidato saidfsecondfilter on adjustment of the connection of shutter opening control means relative to the second filter in accordance with the film speed rating and releasing the guide from the second filter on adjustment relative to the shutter opening control means, cooperating shutter opening and time exposure scales on said time exposure guide and said second filter for determining on adjustment of the second filter when the guide is released therefrom the proper time exposures for different shutter openings, time exposure timing means pre-setta-ble for different time intervals, means'for opening the shutter, means for holding the shutter inopen position to take a time exposure, means operated b the time exposure timing means for releasing the timing means to terminate the exposure and means operatively controlled by said shutter speed control means for selectively rendering said shutter holding means efiective to take a time exposure and inefiective to take an instantaneous exposure.

2. A photographic camera having a rear lens mounting tube, a housing comprising a drum mounted on said lens tube and a cylinder open at both ends and mounted on the forward end of said drum, a partition in said cylinder normal to said lens tube, said partition having an opening coaxial with said lens tube and a translucent screen eccentric to said lens tube, a viewing tube aligned with said screen and in communication with an aligned opening in the wall of the drum normal to the lens tube, a shutter mounted on said partition for controlling the passage of light through the partition opening to the rear lens tube, a forward lens mounting tube mounted on said partition, a wheel on the forward end of said forward lens tube and substantially closing the said operating member being yieldably mounted for movement parallel t the axis of the wheel for uncoupling from said wheel and being normall urged into coupling engagement with the wheel, a shutter speed control means including av speed control cam mounted in said housing, said means including an operating device projecting from said housing and having a toothed portion for engagement with other notches in the periphery of said wheel, said device being mounted for movement parallel to the axis of the wheel for coupling to the wheel and being normally uncoupled from said wheel, said wheel having a light varying portion aligned with the screen and said screen having a variable density pattern to determine a standard of light intensity, said wheel having a film speed rating scale cooperating with inder having a scale cooperating with the operating member of the shutter speed control means to govern the speed setting of said shutter speed control means when said operating device is coupled'to the wheel.

3. Ina photographic camera as set forth in claim,2, shutter. operating means mounted in said housing, means cooperating with said operating means andsaid shuter speed control means for stantaneous exposure and twice to take a time exposure, time exposure timing means including a pre-settable timing member having an adjusting member projecting from said housing, means operatively connecting the shutter operating means to the time exposure timing means to initiate the operation of said timing means on first depression of the operating member of the shutter operating means, means controlled by said time exposure timing means for automatically depressing said operating member a second time upon passage of the predetermined time for which said timing means is 'pre-set.

4. In a photographic camera as set forth in claim 2, a time exposure guide comprising a member journaled on the forward lens mounting tube and having an operating portion extending out of the housing, said operating portion being yieldable for movement parallel to the axis of the wheel and having teeth on its opposite surfaces, the teeth on its forward surface being adapted to engage other notches in the periphery of the wheel to couple the time exposure guide to the wheel during adjustment of the wheel when the shutter opening control cam is uncoupled from the wheel, the cylinder of the housing. having an arcuate edge with notches to engage a tooth on the rear surface of the operating portion of the guide to secure said guide against movement when it is uncoupled from the wheel and the wheel rotated to measure the light, intensity, said wheel and said time exposure guide having cooperating shutter opening and time exposure scales to indicate on adjustment of the wheel to measure light intensity proper shutter openings for different time exposures.

5. In a photographic camera, the combination of an adjustable shutter, light measuring means comprising a pair of cooperating shiftably mounted filter members, one of said filter members having sections of different ranges of. light transmissibility, the other filter member being constructed to vary the light transmitted in predetermined ratio to the degree of movement of said member, shutter speed control means for selectively setting the shutter for the taking of instantaneous exposures of different speeds and for the taking of time and bulb exposures and operatively connected to said one filter member for selectively rendering different light transmission ranges of said filter member efiective on setting of the shutter for the taking ofinstantaneous, time or bulb exposures, shutter opening control means operatively connected with the other filter member for setting the shutter for differentsize openings in accordance with the movement of said other filter member to measure the light intensity. DENNIS B. DORSEY.

(References on following page) :'2;,194,152' "Riszdorfer Mar. 19, 1940 10 Name Date Fischer Ju1y 23, 1940 Leitz et a1 Sept. 16, 1941 Tonnies Mar. 31, 1942 Bath June 8, 1943 FOREIGN PATENTS Country Date Italy Y Septyll, 1935 Great Britain May 4, 1936 

